Effects of the Extremely Low Frequency Electromagnetic Fields on NMDA-Receptor Gene Expression and Visual Working Memory in Male Rhesus Macaques

Abstract

Introduction:The present research aimed to examine Visual Working Memory (VWM) test scores, as well as hormonal, genomic, and brain anatomic changes in the male rhesus macaques exposed to Extremely Low Frequency Magnetic Field (ELF-MF).Methods:Four monkeys were exposed to two different ELF-MF frequencies: 1 Hz (control) and 12 Hz (experiment) with 0.7 μT (magnitude) 4 h/d for 30 consecutive days. Before and after the exposure, VWM test was conducted using a coated devise on a movable stand. About 10 mL of the animals’ blood was obtained from their femoral vain and used to evaluate their melatonin concentration. Blood lymphocytes were used for assaying the expressions of N-Methyl-D-aspartate NMDA-receptor genes expression before and after ELF exposure. Anatomical changes of hippocampus size were also assessed using MRI images.Results:Results indicated that VWM scores in primates exposed to 12 Hz frequency ELF increased significantly. Plasma melatonin level was also increased in these animals. However, these variables did not change in the animals exposed to 1 Hz ELF. At last, expression of the NMDA receptors increased at exposure to 12 Hz frequency. However, hippocampal volume did not increase significantly in the animals exposed to both frequencies.Conclusion:In short, these results indicate that ELF (12 Hz) may have a beneficial value for memory enhancement (indicated by the increase in VWM scores). This may be due to an increase in plasma melatonin and or expression of NMDA glutamate receptors. However, direct involvement of the hippocampus in this process needs more research.

Alterations of Cognitive Functions Following Violent and Football Video Games in Young Male Volunteers: By Studying Brain Waves

“…Due to the fat-soluble nature of cortisol, it easily flows in the saliva. Therefore, salivary cortisol and its variations can be used as a measure of changes in plasma cortisol and the activity of the HPA axis and the adrenal gland ( Smeets, Otgaar, Candel, & Wolf, 2008 ; Kazemi et al, 2017 ). Also, the sympathetic-adrenal-medullary axis, as a second potent immunoregulatory and anti-inflammatory stress-response system, stimulates the sympathetic system and increases the secretion of noradrenalin ( Chrousos, 2009 ; Feinstein, Adolphs, Damasio, & Tran, 2011 ).…”

Extremely low frequency magnetic field induces human neuronal differentiation through NMDA receptor activation

“…Previous studies on effects of ELF EMF on NMDA receptors report altered ligand binding (Manikonda et al 2007) and transient elevations in subunit expression (Li et al 2014;Kazemi et al 2018) but do not address possible effects on activation. Considering the above information, it is tempting to hypothesize NMDA receptors to be the starting point of ELF MF effects on neural progenitors.…”

The Effect of Electrical Fields From High-voltage Transmission Line on Cognitive, Biological, and Anatomical Changes in Male Rhesus macaque Monkeys Using MRI: A Case Report Study

“…Electric fields and currents exist in the body of all living organisms that act as a contributor to physiological control mechanisms such as the nervous system, cell death, growth, tissue growth and repair (8,9). The EMFs are associated with many symptoms such as dizziness, tinnitus, weakness and fatigue, blurred vision, and drowsiness during work, as well as the emergence of unknown diseases, altered blood composition, impaired musculoskeletal system, and immune system dysfunction among animals and humans (10)(11)(12)(13). Impaired secretion of hormones may lead to behavioral and cognitive disorders (1).…”

“…Impaired secretion of hormones may lead to behavioral and cognitive disorders (1). Accordingly, EMFs adversely affect the secretion of protein and amine hormones by activating to G-protein coupled receptors and membrane enzymes (10,11). The ACTH secreted from the anterior pituitary, acts to stimulate the adrenal cortex hormones and regulates the secretion of cortisol and adrenaline (10,14).…”

“…Results from many studies indicated themes from simulated high voltage towers, reduce melatonin secretion resulting in sleep, attention, learning and memory disturbances, and development of mental illness such as depression in Rhesus monkey (1, 7,10,11,[14][15][16][17][18][19][20][21].…”